Locking device



Sept.. 24, 1935. F, H, MUSSLER mmm LOCKING DEVICE Filed Oct. 25, 1934 Patented Sept. 24, 1935 UNITED STATES OFFICE LOCKING DEVICE Frank H. Mussler, Stratford, Conn., assignor to The Bullard Company, a corporation of Coni necticut Application October 25, 1934, Serial No. 749,945

Claims.

This invention relates to means for clamping tool head rails, slides, or similar machine tool elements, to their ways, slides or locks.

Among the general objects of the invention is to provide convenient, simple and efficient means for securely locking associated elements against inadvertent, or accidental, movement or chattering.

Another object is to provide such an instrumentality particularly adapted to overcome the inherent diiliculties found in the clamping of long bars or rails; the diiiiculties of which may arise from the distance between the bearing surfaces.

Another important object is to provide means for eifectively locking an element through the actuation of a single control means such that a single lever may be used to eiect binding at a multiplicity of points.

Another object is to provide a locking means operable to provide, in response to minimum effort of the operator, a powerful, equalized pressure on the several binding surfaces, and one in which ease of adjustment and maintenance of pressure is a characteristic feature.

Another object is to provide the equalization mentioned without recourse to lost motion equalizers, or equivalent adjunct parts and equipment; the equalization in the present device .being inherent in the structural design.

Another object is to provide a device incorporating a novel, simplied operating system; the transfer of motion through which seeks to minimze the number of parts and to increase efficiency and accuracy of motion transmission, and to avoid friction and other torque increasing or motion loss factors.

Other objects and features of the invention include the provision of a device susceptible to economic manufacture and maintenance, and not requiringy a skilled operator, or time lost, in operation.

Other objects and features will be apparent from a consideration of the drawing taken in connection with the following specification.

While the inventive concept is susceptible to modified forms and structural variations, a preferred embodiment is herein presented, which is adapted for use in connection with a tool head rail such as may be used on a vertical boring mill, or lathe. It is, however, obvious that the invention is applicable to various types of machine tools. The illustrative embodiment of the invention is characterized by the provision on the rail, or equivalent movable member, of binding bars preferably fulcrumed near the binding point, so as to obtain leverage, and actuated from their opposite ends; the bars Abeing inherently flexible so as to compensate for differences in pressure, one between another. The invention is also characterized by the provision of a single operating member, preferably in the form of a rocker arm for all the bars, which may be moved by rectilinear movement of a single operating member, the handle of which v may be positioned at the end of the rail. The individual flexibility of the bars avoids the necessity of lost motion linkager and the arrangement of parts permits the use of individual adjusting means, as illustrated, so as to compensate for l5 wear and discrepancy between the required movement of the various binding bars.

A perusal of the accompanying drawing will sho-w the structure as being flexible and that an equalized pressure at all contact, or bind, points on the ways may be obtained and retained through proper adjustment. It will also be noted that, in a non-rotary actuating rod having a slight reciprocating, or longitudinal, movement, it is possible to abolish excessive torque and minimize rotary friction such as may be anticipated in a construction whereby the rotary rod may have primary and secondary levers fixed thereto at each end for actuating the clamps.

In the drawing:

Figure l is a plan view of the structure embodying my invention.

Figure 2 is a front elevation of that structure shown in Figure 1.

Figure 3 is a sectional elevation taken on line 35 1 3 3 of Figure 2.

Figure 4 is an end elevation of the structure shown in Figure 2. i

In the drawing, a tool head rail is indicatedgby the numeral Il). Although no tool head is shown, it is to be understood the rail may be adapted to carry one or more tool heads which generally include carrying a saddle tool slide; the slide being usually adapted to be reciprocated to and from the work which is carried on a work table revolvably mounted in the base of the machine. 'Ihe rail, lil, is slidably mounted on ways, or locks, il, formed upon up-standing columns, l2, of the4 base of the machine.

For moving the rail, lll, over the ways, ll, actuating screws, i3, threadedly engage rail lugs, or nuts, LBA; the screws, i3, being connected with a suitable source of power such that the screws may be actuated to raise, or lower, the rail carrying the tool heads as required.

For securing the rail in adjusted position as moved by the screws, I3, horizontally positioned clamping bars, I4, four being here shown, are located at the rear of the rail IU; two at the top and two at the bottom. The points of Contact, or bind, on the ways, or locks, are generally indicated at I5. Each bar, I4, is secured to the rail I0, at its outer end by ball-headed bolts, I5; the bars being fulcrumed thereon for restricted pivotal movement.

The over-lying relation of the ends, I5, of the bars, I4, at the back of the ways, I I, provides for a clamping of the rail, I0, to the ways upon pivotal movement of the bars upon their bolts, I6. Thus, when the opposite ends of the bars, I4, are rocked outwardly, the ends, I5, move inwardly towards the flanges of the ways, thus causing an effective locking bind at the points, I5, and also upon the front surface of the ways.

For pivotally moving the bars, I4, to bind, or release, the rail, vertically positioned fulcrum levers, I8, pivoted at I9 are provided; their fulcrumed ends having actuating heads, ISA, each head being adapted to engage the inner ends of a pair of the bars, I4. In order to provide adjustment between bars of a pair, the heads, ISA, preferably engage the bars indirectly through the medium of adjusting screws I1. Thus, adjustment and compensation for wider, or for inherent, elasticity of the bars may be readily made.

The levers, I8, are, themselves, operated by the at arm, 2l, of the bell crank, 22, located rearward thereof and, as in the case of the bars, I4, adjustment between the movement of the levers, I8, in response to pivotal movement of the crank, 22, is attained through adjustable contact screws, 20, carried by the inner ends of the levers, I8. Thus, as the crank, 22, pivots upon its axis, the levers, I8, will be rocked, each proportionately to the setting of its screw, 20, and the bars, I4, are, in turn, rocked proportionately to the adjustment of their respective screws, I'I. For actuating the crank, 22, its upper end is provided with a forwardly extending arm, 23, adapted to engage a horizontal, slidably mounted, actuating rod, 24, which is notched to receive the head of the lever and supported at each end in the rail as indicated at 25 and 26. Thus, as the rod reciprocates, such movement will be relayed, as pivotal movement, to the crank, 22, and then through to the bars, I 4, as before described.

At the right hand end of the rod, and mounted on the same, is an inwardly extending cam-faced sleeve, 2'I, slidably mounted, in the rail and keyed to prevent rotary movement and which is adapted to thrust against a shoulder on the end of the rod. A manually operated lever, 28, with a similar cam-faced head, 28A, is loosely pivoted on the rod, 24, and is restrained against bodily movement, or end thrust, by engagement with the rail. It is to be understood that, when the clamping lever is in its outward, or released, position, the slanting cam surface of the head, 28A, will permit the sleeve and rod to move to the left, as in Figures 1 and 2, and thus will relieve pressure on the bars. Upon reverse rotation of the head, 28A, the camming surfaces will co-operate to give a right hand thrust to the rod at the end of which, dwell areas of the sleeve and head provide for retention of parts in the adjusted, or binding, position, such position being shown in Figure 2.

An important feature of the construction is the ilexibility of the bars, I4, which acts to provide compensation between unequal movement of parts and which thus, without the necessity of structural equalizing means, insures equal binding 5 forces applicable upon the operation of the single lever. Also, such ilexing of the bars acts to maintain the binding force after the operating means have come to rest with the parts as shown in Figure 2. With respect to these bars, it will be 10 understood that their flexibility need only be slight such as is inherent in bar steel or iron. Thus, though the device makes important use of this flexing, no departure from the strength, or normal rigidity, of such structures is contemplated.

While the preferred embodiment of the invention has been hereinbefore mentioned as being adapted for use in connection with a tool head rail, such as used on a vertical boring mill, or lathe, it is to be understood that various changes and modifications of the invention may be resorted to such that the same may be applicable to a variety of slidable elements of machine tools without departing from the spirit and scope of the invention as outlined in the appended claims.

Having set forth the nature of my invention, what I claim is:

1. In a device o1" the character described, a pivotally mounted locking arm, an operator therefor and adjustable means between said arm and operator variable to adjust the movement of the arm in response to movement of the operator, said operator including a pivoted member for moving said arm and a reciprocating member for moving said pivoted member.

2. In a device of the character described, a pivotally mounted flexible operating arm, an operator therefor and adjustable means between said arm and operator variable to adjust the movement of the arm in response to movement of the v operator, said operator including a pivoted member for moving said arm and a reciprocating member for moving said pivoted member.

3. In a locking device, two pairs of flexible locking arms mounted for pivotal movement, a single operator for both pairs of said arms, adjustable means between said operator and each pair for individually adjusting the amount of movement to each pair in response to movement of the operator and adjustable means on each arm of each pair for adjusting the amount of movement of each arm with respect to the movement of the other arm of the pair.

4. In a locking device, two pairs of iiexible locking arms mounted for pivotal movement and a single operator for both pairs of said arms, said operator including a pivotally mounted member and reciprocating bar for moving said pivotally mounted member.

5. In a locking device, two pairs of flexible locking arms mounted for pivotal movement, a single operator for both pairs of said arms, said operator including a pivotally mounted member and reciprocating bar for moving said pivotally mounted member and means for reciprocating said bar including a pair of co-acting cam surfaces, one of which is secured to the bar and is movable longitudinally therewith in response to movement of the companion cam surface.

FRANK H. MUSSLER. 

